Coarse-grained modeling of multi-component nanomaterials and interfaces.

Multi-component nanomaterials (MCNMs), composed of distinct components with at least one nanoscale dimension, are increasingly relevant across industrial sectors such as construction, healthcare, and energy. By integrating multiple components, these materials exhibit enhanced or completely new properties, unachievable by their individual components. However, MCNMs pose significant design, environmental, and safety challenges. In this framework, molecular simulations are essential for understanding the nanoscale physicochemical properties of MCNMs, enabling their optimization and safe implementation. This thesis, developed within the the H2020 EU SUNSHINE (Safe and Sustainable Design for Advanced Materials) project, presents a computational investigation of different MCNMs and their interfaces using Molecular Dynamics simulations at a coarse-grained (CG) resolution with the Martini force field. While this approach enables the simulation of relevant time and length scales, it also introduces challenges due to limitations of the force field in accurately modeling solid-liquid and liquid-vapor interfaces. This work proposes strategies to overcome these limitations, paving the way for reliable simulations of MCNMs in different environments. For instance, we investigated water intrusion and extrusion in grafted nanopores, uncovering microscopic mechanisms governing these processes and their influence on energy dissipation, with implications for energy storage and damping technologies. Additionally, this thesis includes the development of a CG chitosan model, which will enable the study of a chitosan-functionalized graphene oxide material with flame-retardant properties, in the framework of the SUNSHINE project. The results of this thesis and its methodological advancements contribute to the rational design of next-generation MCNMs, aligning with the goals of a sustainable and safe innovation.